Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that your players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Example:
I update my answer with some example pictures. The following photographs show the funeral ceremony and cremation of a respected lord, with a druid calling the gods in his favor. No longer visible: on top of the pyre we had placed a man-sized dummy wrapped in white linens, which was carried in on the shields of 4 warriors.

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that your players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that your players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Example:
I update my answer with some example pictures. The following photographs show the funeral ceremony and cremation of a respected lord, with a druid calling the gods in his favor. No longer visible: on top of the pyre we had placed a man-sized dummy wrapped in white linens, which was carried in on the shields of 4 warriors.

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that you'reyour players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that you're players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that your players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can add a lot to the atmospherework wonders. Obviously you needneed to know what you are doing, and you need to be in total controltotal control of the situation in which the fireworks are handled. Don't(Don't screw around. (Examples) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.)

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that you're players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can add a lot to the atmosphere. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. Don't screw around. (Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.)

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that you're players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

For Gods sake, no cell phones.

Sound

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).

Theatrics

Make sure all your scenes are well rehearsed. Nothing will take you out of a scene quicker than some performer who forgot his script.

Chanting/incantations/songs/spells are a great way to A) build up atmosphere, and B) make it very clear to all participants, that they are attending a ritual of some sorts.

Make sure people will remember their texts. If they can't learn them by heart, use a prop (book, scroll, inside of their sleeve/hand...) which they can use as a cheat sheet. This is still a lot better than people forgetting their text midway through an incantation.

Come up with a style of movement for your chanter and use it throughout. This could be slow walking or praying movements (think of monks), this could be wild gesticulation or even trance-like dancing, ... Be consistent. Of course this should also be rehearsed if possible.

Obviously all attendants, foremost the chanter, will need a good costume. If that is not possible, try limiting visibility (e.g. at night).

Ambient lighting

In our LARP all the really good and intense rituals were done at night:

Bonfires add a lot to the atmosphere

Use torches, lanterns, candles, the more the better

Fireworks can work wonders. Obviously you need to know what you are doing, and you need to be in total control of the situation in which the fireworks are handled. (Don't screw around.) Examples that worked well for us: small sparkling candles, smoke powder, lycopodium seeds.

No distractions

Find a good secluded spot, away from your camp, from roads/paths and other distractions

As far as possible try to make sure that you're players are into this ritual stuff. E.g. find a way to distract players who aren't with some other quest/... One snicker or snide remark at the wrong time can destroy all your efforts of building up atmosphere.

Everybody stay in character.

For Gods sake, no cell phones.

Sound

Make sure all participants can hear what they need to (chants, incantations, ...). This is especially important if your mage/druid/warlock/witch/... is wearing a mask, which can muffle their voice.

If you use music, I'd suggest using live instruments as far as possible. Relying on electronics can be tricky, especially if you work outdoors (We had it all: moist weather/rain can short circuit devices, batteries won't last if its cold, software bugs will make you cry).

If the weather is bad this can be an advantage, as it can add a dramatic atmosphere. But keep in mind it will also be unpleasant to stay out in the rain and cold for a long while. Also your incantations and music need to be a good deal louder to be heard over the rain (and/or wind).